2550409

Appears in sequences

• a(n) = a(n-1) + a(n-3) + a(n-4), a(0) = a(1) = a(2) = 1, a(3) = 2.at n=32A006498
• Squared Fibonacci numbers: a(n) = F(n)^2 where F = A000045.at n=17A007598
• Squares of odd Fibonacci numbers.at n=11A014728
• Lesser of twin numbers (differing by 1) of the form F(i)^2 + F(j)^3 (A045704), where F() are Fibonacci numbers.at n=26A063907
• a(n)-1, a(n) and a(n)+1 form three consecutive integers that can be factored into Fibonacci numbers.at n=18A065885
• a(n) = Sum_{i = 0..floor(n/2)} (-1)^(i + floor(n/2)) F(2*i + e), where F = A000045 (Fibonacci numbers) and e = (1-(-1)^n)/2.at n=33A074677
• a(n) = (Lucas(4*n+2) + 2)/5, or Fibonacci(2*n+1)^2, or A081067(n)/5.at n=8A081068
• a(n)= 3*a(n-1) -3*a(n-3) +a(n-4), n>6.at n=18A107840
• a(n) = a(n-1) + a(n-3) + a(n-4) for n > 3, a(0) = -1, a(1) = 1, a(2) = 2, a(3) = 1.at n=33A111569
• Number of derangements of [n] avoiding the patterns 123, 132 and 213.at n=31A114215
• a(n) = Product_{k=1..floor((n-1)/2)} (1 + 4*cos(2*Pi*k/n)^2).at n=34A152192
• A product of consecutive doubled Fibonacci numbers.at n=17A166516
• Squares that are a sum of two Fibonacci numbers plus the square of a Fibonacci number.at n=38A179459
• Number of n X 1 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,3,4 for x=0,1,2,3,4.at n=31A195971
• a(n) = F(n+1)^2, if n>=0 is even (F=A000045) and a(n) = (L(2n+2)+8)/5, if n is odd (L=A000204).at n=16A208176
• Primonacci numbers: composite numbers that appear in the Fibonacci-like sequence generated by their own prime factors.at n=13A212875
• Numbers n such that n^2 - 1 is the product of four distinct Fibonacci numbers greater than 1.at n=29A242074
• Number of (2+1) X (n+1) arrays of permutations of 0..n*3+2 with each element having index change +-(.,.) 0,0 1,2 or 2,2.at n=10A264018
• a(n) = a(n-1) + a(n-3) + a(n-4), where a(0) = 1, a(1) = 1, a(2) = 1, a(3) = -2.at n=38A295672
• Number of nX4 0..1 arrays with every element equal to 0, 1 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.at n=14A301960